An Oracle spokeswoman declined comment. Apple and EMC did not immediately respond to a request for comment.

There seems little cause for immediate alarm, according to open-source advocate Florian Mueller, who flagged the Bundeskartellamt notice on his blog Thursday.

"I don't have a crystal ball that would tell me what their business plan with those patents is, but those organizations have a track record and, very importantly, they have a reputation to protect," Mueller wrote. "They all want to enjoy excellent relations with software developers, and software developers expect large players to make reasonable and constructive use of whatever patents they own. I guess that's exactly what will happen in this case."